What is "terpyridine"

n. 1 (context uncountable organic compound English) A tricyclic heterocycle consisting of three linked pyridine rings; it is a tridentate ligand 2 (context countable organic compound English) Any substituted derivative of this compound

Terpyridine (2,2';6',2"-terpyridine, often abbreviated to Terpy or Tpy) is a heterocyclic compound derived from pyridine. It is a white solid that is soluble in most organic solvents. The compound is mainly used as a ligand in coordination chemistry.